Expanding roller underreamer



March 17, 1931. J. J. SANTIAGO 1,796,479

EXPANDING ROLLER UNDERREAMER Filed Oct. 19, 1927 2 Sheets-Sheet l O I22pen/0r.

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March 17, 1931. J. .1. SANTIAGO EXPANDING ROLLER UNDERREAMER Filed Oct.19, 1927 2 Sheets-Sheet 2 l'npezzx' qrv %mea7 San/zaya War/76y PatentedMar. 17, 1931 UNITED STATES PATENT OFFICE SANTIA O, L S A GELE A F RNIA,ASS HQB' IQ JOH L S GELE CAL FQB N A Exraumuc ROLLER vunueauanuaApplication filed October 19, 1927. Serial N'o. 227,107,

This invention relates to expanding reamers of the type used in rotarydrilling or reaming, and usually for underreaming below the casing; thegeneral object of the invention is the provision of a compact, simpleand strong expansive rea-mcr which presents a maximum of cutting edge tothe strata. There are various other objects and correspondingaccomplishments of the invention, but all these will be best understoodfrom the following detailed description of an illustrative specificembodiment of the invention.

The present invention bears certain rela- ,15 tionships to that set outin the application of John Grant, Serial Number 122,340, filed July 14,1926, for expanding well reamer; the application of said John Grantfiled Oct. 10, 1927, Serial No. 225,270 (Case A) 2c and the applicationfiled by me on Oct. 19, 1927, Serial No. 227,106 (Case B this presentapplication being known in the series as Case C The first Grantapplication sets forth an expansive reamer wherein a cutter element,typically an annular roller, surrounds the mandrel and is shiftablelaterally with relation to that mandrel by virtue of longitudinalmovement with relation to the mandrel. The second Grant application setsout a series of such cutter elements mounted on individual mandrelsarranged around the main reamer body, and each shiftable laterally withre.- lation to its individual mandrel pin by virsgs tue of relativelongitudinal movement. My o-pending application identified above setsout a construction wherein the cutter elements, typically annularrollers, surround the main body mandrel and are shiftable go laterallyon that mandrel without relative longitudinal motion to and from anoffset bearing surface, the shifting being accomplished by eccentricaction. This present application deals with an arrangement and ,-3combination wherein a plurality of cutter elements are arranged on aplurality of in? dividual mandrel pins spaced around the main reamerbody, and are shiftable laterally without relative longitudinalmovement. A specific and il ustra iv esign mbodying the features of mypresent invention is illustrated in the accompanying drawings, in which:

Fig. 1 is an elevation of a complete reainer;

Fig. 2 is an enlarged fragmentary longi= tudinal section of thesame'show-ing a cut.- terelement in expanded position;

Fig. 3 is a similar section showing a cut.- ter element in contractedposition;

Fig. 4 is a further enlarged crossrsection showing the cutters inexpanded position and taken on line Lu-st of Fig. 2;

Fig. 5 is a similar section showing the cut tors in intermediateposition; and

Fig. 6 is a similar section showing the cutters contracted.

In the drawings a typical reamer body is shown at 10 having the usualscrew-threaded pin 10a at its upper end for connection to a rotary drillstring. The reamer body may be made in two parts, comprising the bodyproper 10 and a body extension 10?; joined by the usual pin and boxconnection 10c; the extension at its lower end being connected by theusual pin and box connection 11 to a drill bit 12 of any desired type.Water courses l3 and 14 extend longitudinally through body 10 andextension '10?) to con= nect with water course 15 in the drill bit,Through the slotted part of the body the water courses 13 and 14 areconnected by a tube 16 having spaced lines of perforations 16a todeliver water inside the several cut= ting elements and their mountingsto sup ply them with circulation water and to keep them washed cleanthroughout their lengths. As shown in Fig. 4 these perforations arepreferably located so as to deliver water directly onto the severalcutting elements.

It will be understood that a reamer of the type here described may bedesigned. to embody any suitable number of cutting ele= ments; theprinciples of construction and operation concerned herein beingapplicable to any number of cutting elements. For purposes ofillustration I have preferred to show a construction embodying threecutting elements or cutter assemblies; and therefore the body 1.0 isshown as provided with three radial and longitudinally extending slots20 which meet at the center of the body, as is best shown in thecross-sectional views, the circulation tube 16 passing longitudinallythrough the center of the space thus formed. For functional purposes tobe described these slots 20 are each widened out as at 20a in theircentral portions, being there defined by side walls 206 and 200.

Extending longitudinally through each body slot, and mounted at itsupper and lower ends in the reamer body, is a cylindric mandrel pin 25which may either be rotationally stationary or may rotate with thesurrounding eccentric sleeve 26. How-' ever, I prefer to fit the mandrelpins 25 fairly tightly at their upper ends into sockets 27 and at theirlower ends into sockets 28, so that the pins may remain stationary andso that the bearing face where relative rotation takes place will becomparatively longthe whole length of eccentric sleeve 26. Socket 28which takes the lower ends of the mandrel pins extends down wardly tothe body shoulder 29 where body 10 shoulders up against extension 106;so that, by removal of extension 10. the mandrel pins may be slipped outlongitudinally and the whole assembled.

Each mandrel pin has an eccentric sleeve 26 surrounding it, theeccentric sleeve having an eccentric cylindric outer bearing surfacewhich carriers the roller cutter 30. These roller cutters may be, in myconstruction, of some considerable longitudinal extent, so that eachpresents to the strata a long cutting edge. The roller cutters may be ofany preferred construction or design and provided with any preferred ordesired teeth or other cutting formation on their outer faces.

Eccentric sleeves 26 are preferably made in two parts 266 and 260, eachpart being provided with a head 260 which is formed in such a manner asto provide in effect a stop lug which brings up against one of the wallsof the body slot, thus to limit the relative rotations of the eccentricsleeve. For ease and simplicity of manufacture these stop heads 260 canbe made, and are here shown, as eccentric heads of the same eccentricityas, although larger in diameter than, the eccentric sleeves 26. It willbe understood that eccentric sleeves 26 are divided into two halvesmerely for ease of manufacture and assembly; so that the heads 26a maybe made integral with the sleeve halves and the sleeve halves insertedlengthwise into the roller from opposite ends. In operation the sleevehalves rotate together just as though each sleeve were one piece fromend to end. The rollers extend lengthwise on the sleeves from head tohead; the heads are made as short as consistent with good reamer thuseasily disdesign; and the rollers are, as nearly as practicable, ofsubstantially the same length as the slots. This gives a long cuttingedge, and also gives to the roller a very direct support, through theeccentric and mandrel, without putting the mandrel under any largebending stresses.

Fig. 6 shows the contracted positions of the cutters, moved inwardly farenough that the whole tool will pass through the well pipe P. In thisposition the eccentrics 26 are so located that their centers C--1 arelocated inward of the center C of mandrel pins 25. In the drawingscenters C1 are shown located directly radially inwardly of centers Cthatis, directly toward the central axis of the whole tool. In this positionit will be seen that the eccentric outer surface of heads 2611 havebrought up against the walls 20?) of slots 20. The eccentrics cantherefore make no further rotation in a right hand direction in Fig. 6.In this collapsed position of the cutters the tool may be loweredthrough the well pipe P and into the drill hole beneath the pipe. Thenthe whole tool is rotated right-handedly, looking down upon it, and therelative drag due to contact of the cutters and of the eccentrics 26with the walls of the hole then causes the eccentrics to move around ina relative left-hand direction-in the relative directions indicated bythe arrows placed on'those eccentrics in Fig. 5. Walls 200 of slots 20are spaced further from mandrel centers C than are walls 20?), so thatwhen the eccentric heads 26a reach such positions as shown in Fig. 5they will clear walls 200. Accordingly the eccentrics rotate in arelatively left-hand direction until they reach the position shown inFig. 4, where the eccentric centers Cl are located substantiallyradially outwardly from mandrel centers C and where the eccentric heads26a have again brought up against slot walls 20?), as shown in Fig. 4.In this position the eccentric sleeves can make no further movement, thecontact of the eccentric heads with the slot walls act-ing as a movementstop. During continued right hand rotation of the tool for drilling andreaming operations the reaction and drag on the rollers and eccentricsis such as always to keep the eccentric heads 26a up against the limiting stops; and accordingly the cutters remain, during drilling andreaming operations, in their expanded positions.

To contract the cutters it is only necessary to.rotate the tool a shortdistance in a lefthanded direction, when the cutters will be turned backto the position of Fig. 6 by the drag of the strata; or the tool may bepulled up to a position where the upper heads 26a come in contact withthe lower end or shoe of the casing, and then if the tool is rotated alittle to the left, friction of the casing with the heads will causethem to rotate back into the reamer body. At the same time, if a slightupward pressure of the eccentric head is maintained against the lowerend of the casing, the usual conical inner face of the casing shoe will,just as soon as the eccentrics have rotated slightly back from theirpositions shown in Fig. 4, have the action of pressing the eccentricsinwardly rotate them around right-handedlyas the tool is mov d upwardly.For this kind of collapsing action the design, if desired, may beslightly modified to stop the expansive rotation of the eccentricsleeves in a position a little short of the absolutely radial positionshown in Fig. 4, so that the eccentric sleeves will always be rotatablymovable by contact with the conical opening in the lower end of thecasing shoe. And, if the lower end of the casing shoe have a squareedge, instead of an inner conical taper, a bevel 26a, as illustrated inF igs. 2 and 3, applied to the upper edge of upper eccentric head 26a,will have the same action.

I have specifically described this reainer as having rotating rollercutters 30 which surround and rotate directly upon the eccentric sleeves26. It will be understood, however, that the rotating rollers may typifyany kind of cutting element mounted upon the eccentrics and shiftedbodily by rotation of the eccentrics. The construction, however, lendsitself very readily to the very simple shiftable mounting for therotatable roller cutter. And whatever specific kind of cutter may beused, the whole construction will be recognized as very simple andstrong and as affording a comparatively long, effective cutting edgethat is strongly supported on the body against all stresses and thrusts.

I claim:

1. In a tool of the character described, a body with a plurality oflongitudinal slots extending into the body substantially radially andmeeting at its center, the body having a longitudinal water courseformed in part by a central tube that extends through the slotted partof the body, longitudinal mandrel pins mounted in the slots andextending through their lengths and in positions outside the centrallongitudinal tube and parallel with it, eccentric sleeves rotatablymounted on said mandrel pins and of lengths equal to the length of theslots, roller cutters revolubly mounted on said eccentric sleeves and oflengths substantially equal to the slot lengths, and the central tubehaving for each roller a set of longitudinally spaced perforationsadapted to direct fluid upon each roller and eccentric substantiallythroughout their lengths.

2. In a tool of the character body with a longitudinal slot, a

described, a longitudinal mandrel pin extending through the length ofthe slot, a cutter carrying member in the form of an eccentric sleeverevolubly mounted on the mandrel pin, a cutter carried on said sleeve,an eccentric head on the sleeve, and a wall of the slot positioned to beengaged by the eccentric head in two rotative posit-ions of the sleeve.

3. In a tool ofthe character described, a body with a'longitudinal slot,a longitudinal mandrel pin extending through the length of the slot, acutter carrying member in the form of an eccentric sleeve revolublymounted on the mandrel pin, a cutter carried on said sleeve, aneccentric head on the sleeve, and a wall of the slot positioned to beengaged by the eccentric head in two rotative positions of the sleevespaced from each other by an angle of substantially 180.

at. In a tool of the character described, a body with a longitudinalslot, a longitudinal mandrel pin extending through the length of theslot, a cutter carrier comprising an eccentric sleeve rotatably mountedon the mandrel pin, said eccentric sleeve being divided into two partsand each part having at its outside end an eccentric head, a cuttercarried on said sleeve, and the slot having wall portions at its endsadapted to be engaged by the eccentric heads in two different rotativepositions of the eccentric.

sleeve.

5. In a tool of the character described, a body with a longitudinalslot, a longitudinal mandrel pin extending through the length of theslot, a cutter carrier comprising an eccentric sleeve rotatably mountedon the mandrel pin, said eccentric sleeve being divided into two partsand each part having at its outside end an eccentric head, a cuttercarried on said sleeve, the slot having wall portions at its endsadapted to be engaged by the eccentric heads in two dilferent rotativepositions of the eccentric sleeve, and a roller cutter rotativelymounted on said eccentric sleeve and embracing the sleeve partsthroughout their lengths except their heads.

6. In a tool of the character described, a body with a longitudinalslot, a longitudinal mandrel pin extending through the length of theslot, a cutter carrier comprising an eccentric sleeve rotatably mountedon the mandrel. pin, said eccentric sleeve being divided into two partsand each part having at its outside end an eccentric head, the slothaving wall portions at its ends adapted to be engaged by the eccentricheads in two different'rotative positions of the eccentric sleeve, and aroller cutter rotatively mounted on said eccentric sleeve and embracingthe sleeve parts throughout their lengths except their heads, the rollerbeing larger in diameter than the heads, and the slot having arelatively widened medial portion to accommodate the roller and itseccentric movement With the sleeve.

7. In a tool of the character described, a body, a mandrel pin mountedtherein, a cutter carrier comprising an eccentric sleeve rotatablymounted on the mandrel pin, said eccentric sleeve being dividedtransversely into two parts and each part having at its outside end aneccentric head, a cutter mounted on the eccentric sleeve between theheads, and the body having a surface adapted to be engaged by theeccentric heads to limit their rotation and the rotation of the sleeveabout the mandrel pin.

8. In a tool of the character described, a body with a longitudinalslot, a cutter carrying member in the form of an eccentric lying withinthe slot and mounted on an axis longitudinal of the slot, a cuttercarried on said eccentric, an eccentric head on the cutter carrier, anda wall of the slot positioned to be engaged by the eccentric head in tworotative positions.

9. In a tool of the character described, a body with a longitudinalslot, a cutter carrying member in' the form of an eccentric lying Withinthe slot and mounted on an axis longitudinal of the slot, a cuttercarried on said eccentric, an eccentric head on the cutter carrier, anda wall of the slot positioned to be engaged by the eccentric head in tworotative positions spaced from each other by an angle of approximatelyIn Witness that I claim the foregoing I have hereunto subscribed my namethis 5th day of October, 1927.

JAMES J. SANTIAGO.

